Improvement in truss-bridges



iti-teh' Siete? @eine effin JOHN A. MCKAYQOI? AUBURN, INDIAN-A.

Letters Patent No. 111,662, dated February 7, 1871.

IMPROVEMENT IN 'l'RUSS-BRDGES.

The Schedule referred to in these Letters Patent and making part of thesame.

` exact description of the same, reference being had to the accompanyingdrawing making a part of this specification, in ivhicl1` Figure 1v is .atop view;

Figure 2, a side elevation, with a small space att-he vfoot of a bracein section; Y

'Figure 3,21. vertical crosssection through line x.

, Figure 4, a perspective view of one. of the sockets.-

' concussion; and .Y It is accomplished by the use of arnet-allie socketor cap ofpcculiarconstruction which rests on the upper chords and` holdsthe end of the cross counterbraces.' v

In the drawing- A A are the upper chords, connected. by horizontalcounter-braces, B AB, and by the terminal braces B the counter-bracesbeingr bolted together at b '11.

Q C are the lower chords, connected each to the upper one above it bymeansof the vertical double braces ll E' and single braces lf lf".

The lower chords are also connected andulaterally braced by thetitan-timbers G Gr, which are provided with shoulders that iit againstthe chords, holding them apart, as shown in iig. 3, and with gains thatiit around the edges of the side-braces, as shown in Iig. 2, preventinglateral movementeither otward or inward. y'

Such being the general construction of thetruss.

my improvement consists lin the employment of a in etallic cap, M, shownin figs. 1,4, and -5, which is at.- tached to the upper side oi the topchords -bymeaus of pins, r1', projecting down into holes made in thechords, and serves as a socket to confine and hold the l ends ofthecross-braces. n

The braces cross each otherrat the center of the socket, and are bolteddown through it, asv shown at c e.

.Lhe socket is a plate of metal cast with crossed beds or grooves in itsupper side to accommodate the crossed braces, the grooves terminating attheir-.outer end at a wall or flange, c e, against which the ends ot'the timbers abut, and being, of course, open at their inner end.

Between theoutverends oi' the timbers the space may be filled'by are-cntrant angle of the ange, as at a, in iig. 5, or by a solidprojection, as at c, in fig. 4,

Yand a similar angle or projection, i t, maybe cast or formed betweenthe inner ends ot' the grooves to brace the timbers firmly oil thatside.

lo'completc the bridge to which my improvement is shown applied, Iemploy braces E with gains fm m into which the chord-timbers fit.

' Bolts o connect the parts.

Cross-braces 11 are constructed and arranged substantially in the samemanner.

lihe braces E and F are provided with tenons fitting in mortises in thechords, and abutting with their shoulders against the surface ofthechords.

lI.hey are bolted as shown at o o' and r r'.

l'laving thus described my invention, lVhat l claim as new, andl desireto secure by Letters latcnt, is- The caps M M, when constructed andapplied substantially'as and ior'the purposes set forth.

'lhe above specification oi' my invention signed by me this 14th day oi'September, A. 1).1870.

' J. A.l MLKAY. Witnesses DAVID 1I. Uonnlncn,

